The present invention relates to a rolling shutter for wall or roof openings, especially in connection with a turnable roof window. More particularly, it relates to such a rolling shutter which has a rolling shutter web composed of a plurality of rolling shutter bars movable from one another to form light gaps, a rolling shaft for winding an unwinding the rolling shutter webs, supports for rotatably supporting the rolling shutter shaft, two parallel side parts connected with the supports and used for guiding the lateral ends of the rolling shutter web, and an actuating device. The latter includes a mechanism for performing the opening movement of the rolling shutter web, and a pulling device engaging the free front end of the rolling shutter web and performing or contributing to its closing movement.
Rolling shutters for roof windows or the like are known in many various embodiments. They serve mainly for closing of roof windows mounted in inclined roof surfaces and including blind frames fixedly mounted in the roof and a window blade turnable or tiltable mainly about a horizontal axis. Such roof windows are usually identified as roof residence window, roof surface window or the like.
In a known rolling shutter of the above mentioned general type, disclosed for example in the German documents DE-OS 2,906,871 and 2,906,913, the pulling device serves the purpose of activating or supporting the closing movement of the rolling shutter for the case when the side parts are arranged not vertically or at least not with such inclination that the rolling shutter web during release of the opening mechanism runs itself to the closing position due to its force of gravity. The pulling device is formed as a special rolling spring. In another known rolling shutter of the above mentioned type disclosed for example in German document DE-GM 8,505,823, the pulling device is formed as a pulling cable which is provided additionally to a pulling cable which forms the opening mechanism, so that by pulling of one of the two pulling cables an opening movement or a closing movement can be performed. Similar devices are also disclosed in other variants for example in the German documents DE-OS 2,802,078; 2,742,787 and 3,507,015.
For all these constructions of the rolling shutters it is common that they cannot provide sufficient safety in that during closing of the rolling shutter the light gaps located between the individual rolling shutters bars, lamellas or the like, are closed. This is true especially when the pulling device engages at the frontmost rolling shutter bar and the rolling shutter must be closed with partially open, approximately horizontal or upwardly inclined window blade. Regardless of this, the known rolling shutters have the tendency to press the closed rolling shutters bars o lamellas from one another in the event of moist frost or snow, thereby ice and snow can accumulate in the light gaps and cause damages to the rolling shutter web. Moreover, the conventionally utilized rolling shutter webs in the case of glaciation or dirtying of the guides provided in the side parts have the tendency of canting laterally, which can also cause damages to the rolling shutter webs.